Annika Åström

Consumer perceptions of food products involving genetic modification—results from a qualitative study in four Nordic countries

1. The present study addresses consumer acceptance of food products involving the use of different applications of genetic modification in four Nordic countries. Three food products were used as examples: hard cheese, hard candy, and salmon. Three types of applications of genetic modification were investigated: modification of the raw material, use of genetic modification in enzyme production, and direct use of genetically modified microorganisms. In addition, three levels of presence of the genetically modified material in the final product were investigated: not present, present, and present and living/able to function. 2. The results from consumer samples in Denmark, Finland, Norway and Sweden are remarkably similar, showing a strong stability in consumer reactions to the use of genetic modification in food production in these four countries. 3. Consumer perception is characterised by a basic dichotomy of GM and non-GM products. Being non-GM is regarded as a major benefit in itself. When a product involves genetic modification, this elicits numerous negative assocations, of which the strongest ones are ‘unhealthy’ and ‘uncertainty.’ 4. The level of presence of the genetically modified material in the final product has a clear impact on consumer acceptance. When the GM material is present and viable/able to function, acceptance is lowest. 5. The type of application of genetic modification has an impact on consumer acceptance as well, but it differs across products. Still, there is a clear tendency that acceptance of salmon products where the salmon itself was genetically modified was lowest among all products tested. 6. The consumer benefits which the application of GM brings about (e.g., improved taste, functional benefits, environmental benefits) are largely perceived, but cannot overcompensate for the negative associations to GM. In some cases, a supposed benefit (e.g., faster growth of salmon, leading to reduced energy costs) was actually perceived as a disadvantage. Benefits combining personal tangible benefits with societal relevance (e.g., a low calorie candy which can be consumed by people suffering from diabetes) may have most positive impact on consumer acceptance.

Influence of the microstructure on the sensory quality of whey protein gels

Abstract A full two-level factorial experimental design was used to study particulate whey protein gels. The processing conditions, pH, heating rate and the addition of salt were used as design factors. The results were evaluated by using a response surface model, and analysis of variance, M(ANOVA), was performed. The microstructure of particulate whey protein gels has been characterized previously, and the two-dimensional images from light microscopy and transmission electron microscopy were quantified by a stereological approach, while the more three-dimensional scanning electron micrographs were quantified by an expert panel of microscopists. In this study the texture of the same gels was analysed by a sensory panel. Correlations were made between the microstructure and sensory descriptors, and the panellists were able to detect differences between very small particles μ m 3 in volume. The sensory descriptors grainy appearance, gritty texture, creamy texture and tendency to fall apart had a logarithmic dependence on the microstructural parameters, particle size, and size of small and large pores. Multivariate techniques were used to create models to describe groups of the sensory descriptors by some of the microstructural parameters. A model with good correlation (r~ 0.8–0.9) was found for grainy appearance, gritty texture, creamy texture and falling apart. They were all dependent on the star volume of particles and small and large pores. The soft and springy textures were influenced by combinations of microstructural parameters, where the formation of strands into strings of beads or in clusters and conglomerates seemed to play an important role. The sticky texture was negatively correlated to the proportion of threads within the pores.

Texture as a reflection of microstructure

Abstract The perception of texture has been correlated to the microstructure of particulate whey protein gels. A full, two-level, factorial experimental design was used in which the processing conditions, pH, heating rate and addition of salt were used as design factors. The texture of the gels was analysed by a sensory panel, and the microstructure was analysed by light and electron microscopy. The microstructure was quantified by using different types of image analysis. In this study of particulate whey protein gels, the test principles of analysing texture were divided into two groups: destructive tests and non-destructive tests. The microstructural parameters can also be divided into two groups: overall network dimensions (pore size and particle size) and strand characteristics. The texture as measured with destructive methods was sensitive to overall network dimensions, whereas texture as measured with non-destructive methods was sensitive to the strand characteristics of particulate protein gels.